This invention relates to a low impedance multiple capacitor assembly, and more particularly to such an assembly having low impedance over a broad frequency spectrum.
The connection of electrolytic capacitors in parallel by users to increase the total effective capacitance and to reduce the effective impedance at low frequencies is well known. Such multiple capacitor assemblies also generally exhibit a lower impedance at high frequencies, in which instance the effective series resistance (ESR) and the effective series inductance (ESL) of the individual capacitors tend to become the dominant factors determining the total effective series impedance (Z) of the individual capacitor packages. The ESL of a typical electrolytic capacitor is largely attributable to the leads of the capacitor package. Low impedance electrolytic capacitor packages have been devised employing a plurality of capacitor sections connected without leads to an internal low impedance stripline. Such constructions are described by Puppolo et al in U.S. Pat. No. 3,654,524 issued Apr. 4, 1972.
However, the costs of such prior art construction tend to be high, and a simpler but similar multiple capacitor section package employing tail connection of sections to a stripline is described by Markarian et al in pending U.S. patent application Ser. No. 358,207 filed May 7, 1973 toward reducing these costs. Although these multiple section packages provide excellent filtering performance in d.c. power supplies that may be used in computers or that may be of the relatively high frequency switching regulator type, the demand for even lower costs for such capacitors prevails.
It is therefore an object of this invention to provide a multiple electrolytic capacitor assembly having a low impedance over a broad frequency spectrum and having very low cost.